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111.
A single high-dose cycle of chemotherapy with stem cell support can produce disease-free survival of 15-20% for at least 3 years in women with responding stage IV breast cancer. North American Autologous Bone Marrow Transplant Registry data suggest that a complete response (CR) is the single most important prognostic factor associated with prolonged disease-free survival. Therefore, if sequential high-dose chemotherapy can increase the CR rate, then perhaps an increased proportion of patients will remain disease free. Women with at least a partial response (PR) to induction chemotherapy received three separate high-dose cycles of chemotherapy with peripheral blood progenitor support and granulocyte colony-stimulating factor. The first intensification was a dose escalation of paclitaxel (400-825 mg/ m2), the second intensification was melphalan (180 mg/m2), and the third intensification consisted of 6000 mg/m2 cyclophosphamide (1500 mg/m2/day), 500 mg/m2 thiotepa (125 mg/m2/day), and 800 mg/m2 carboplatin (200 mg/m2/day; CTCb). Thirty-six women were enrolled and 31 completed all three cycles. After the paclitaxel infusion most patients developed reversible predominantly sensory neuropathy. Of the 19 patients with measurable disease, 6 converted to CR, 7 converted to a PR* (the complete resolution of all soft tissue or visceral disease with sclerosis of prior lytic bone lesions), and 2 had a further PR for an overall response rate of 79%. Two patients had no further response and disease in two patients progressed, and thus they were taken off the study before CTCb. Seventy-eight percent are progression-free at a median follow-up of 14 months (range, 3-24+). Three sequential cycles of high-dose chemotherapy are feasible and were administered in this study with no mortality. Single agent paclitaxel at doses up to 825 mg/m2 were well tolerated with moderate reversible toxicity.  相似文献   
112.
In this study, the authors examined age differences in social network characteristics (SNC) among Hong Kong Chinese. The sample consisted of 596 Chinese adults, ranging from 18 to 91 years old. Age was positively associated with close social partners and negatively associated with peripheral social partners. For individuals who were more likely to define the self as interconnected with others (i.e., interdependent self-construal), increasing age was associated with a greater number of close social partners. The negative association between age and the number of peripheral social partners, well-documented in the Western literature, was found only among Chinese adults with lower interdependence but not among those with higher interdependence. These findings highlight the importance of examining the underlying mechanism rather than a particular pattern of SNC across cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
113.
From structural analysis we have shown in a previous investigation that the series TlBa2Ca n Cu n+1O2n+5 and Tl2Ba2Ca n Cu n+1O2n+6 are composed of superconductor-semiconductor arrays. In this paper, we demonstrate that the unit cell of the Tl2Ba2Ca n Cu n+1O2n+6 series can further be viewed as composed of a composite block of superconductor-metal-semiconductor, where TlBa2CuO5 is the fundamental superconductor, TlO the metallic unit, and CaCuO2 the semiconductor block. It is indicated that theT c of Tl(2201) can be deduced from that of Tl(1201) based on Kresin's model of composite systems.  相似文献   
114.
Estrogen supplementation in postmenopausal women offers significant cardiovascular protection. The mechanism for this benefit is unclear but may be due to an interaction of estrogen with the blood vessel wall (vascular smooth muscle and endothelium). We examined the response of weight-matched female and male endothelium-intact and -denuded aortae to 17 beta-estradiol, its interaction with noradrenaline, and the effect of N-nitro-L-arginine. Estradiol produced relaxation responses that were significantly greater in female endothelium-intact preparations. This response was sensitive to N-nitro-L-arginine, while the response to 17 beta-estradiol in male endothelum-intact and both female and male endothelum-denuded preparations was resistant. Estradiol also inhibited contractions to noradrenaline, which was more pronounced in the female endothelium-intact aortic rings. These data imply that estradiol interacts preferentially with the female vascular endothelium, but there exists an endothelium-independent process that can also be activated in the male aorta. Further studies are warranted to elucidate these differential mechanisms.  相似文献   
115.
1. The obese gene product leptin, secreted exclusively from adipocytes, was discovered to serve as a satiety factor and to play an important role in regulating body weight. In adults, the serum leptin level reportedly increases with the degree of obesity. Leptin receptors are expressed in various tissues, and recent in vitro studies suggest a role for leptin in haematopoiesis. 2. The present study was designed to clarify the relationship between serum leptin and body mass index, peripheral blood cell counts, serum cholesterol, high-density lipoprotein-cholesterol, insulin and cortisol levels in 299 Japanese male adolescents aged 15-16 years. 3. With simple linear correlation, log [serum leptin] showed a strong correlation with body mass index (r = 0.56), log [insulin] (r = 0.36) and leucocyte count (r = 0.22) (P < 0.001 for all). There were also correlations with systolic blood pressure, erythrocyte count, haematocrit and high-density lipoprotein-cholesterol (P < 0.01 for all). Even after adjustment for body mass index and log [insulin], log [leptin] correlated with leucocyte (P = 0.004) and erythrocyte (P = 0.057) counts. Stepwise multiple regression analyses revealed log [leptin] to correlate significantly with body mass index, log [insulin] and the leucocyte count (P < 0.005 for all, r2 = 0.399). 4. To our knowledge, this is the first clinical study to show the possible association of serum leptin level with blood cell counts, independent of body mass index and serum insulin. We conclude that these data further support a role for leptin in haematopoiesis.  相似文献   
116.
Power control is essential in the use of direct-sequence code-division multiple-access (CDMA) techniques over fading radio channels. The paper investigates a feedback power control approach that allows power commands to be updated at a higher rate than the rate of multipath fading. The signal and interference statistics as received at the base stations after power control are obtained for a simulated CDMA system which includes multiple base stations with diversity receivers and a large number of power-controlled users continuously moving at various speeds. The authors show that often-used analyses based on perfect average power control lead to optimistic capacity results (by about 25%) because interference is underestimated by as much as 1 dB  相似文献   
117.
Models are developed for the primary site and the primary copy locking schemes. These models are then analyzed to obtain important analytic results which enable us to conveniently make comparisons of the two locking schemes in terms of their processing times for update requests as well as other design decisions. The analysis follows an approach which is based on a systematic assignment of comparable values to corresponding parameters in the two models.  相似文献   
118.
Emission from an irregular snow layer is modeled by a layer of Mie scatterers using the radiative transfer method. Comparisons are made with measurements showing snow wetness effects and rough air-snow boundary effects. For convenience of reference, theoretical model behavior is also illustrated.  相似文献   
119.
120.
It is shown that the controlled use of optical crosstalk can induce switching between bistable soliton states in a fiber whose intensity-dependent refractive index is described by the linear plus smooth step model. The closely related phenomena of soliton fission, soliton fusion, radiation stripping, and the soliton transparency-extinction transition are also examined. The evanescently coupled model equations use are discussed, and numerical results are given. It is stressed that the general features of the crosstalk-induced switching and related phenomena do not depend on the specific nonlinearity (the LSS model) chosen  相似文献   
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